William Johnston & Company Limited offer Metallic Ring Type Joint gaskets (RTJs) which are manufactured according to the API 6A and ASME B 16.20 standard for applications at elevated temperatures and pressures.
The small sealing area with high contact pressure results in an excellent seal with high integrity.
Shape and Construction
| STANDARD MATERIALS - STANDARD MATERIALS RECOMMENDED BY THE ASME B16.20 | ||||
| ASTM | EN Material No | Maximum HB | Maximum HV | Material code |
| Soft Iron | 1.1003 | 90 | 56 | D |
| Low CS | 1.0038 | 120 | 68 | S |
| A182-F5 | 1.7362 | 130 | 72 | F5 |
| AISI410 | 1.4000 | 170 | 86 | S410 |
| AISI 304 | 1.4301 | 160 | 83 | S304 |
| AISI316 | 1.4401 | 160 | 83 | S316 |
| AISI 347 | 1.4550 | 160 | 83 | S347 |
| DIMENSIONS - STANDARDS FOR RING JOINT GASKETS USED WITH FLANGES | ||
| Ring Joints Gaskets Style | Ring Joints Gaskets Standard | Flange Standard |
| R | ASME B 16.20 API 6A | ASME B 16.5 ASMEB 16.47 |
| RX | ASME B 16.20 API 6A | API 6B |
| BX | API 6A | API 6BX |

For more information about our Metallic Gaskets that are available world wide, contact us on +44 (0)141 620 1666, Email us or simply complete our online Enquiry Form.
